the World Wide Web at:The online version of this article, along with updated information and services, is located on www.asas.org at Bibliotheque De L'Univ. Laval Section Des Acquisitions on September 10, 2010. jas.fass.org Downloaded from ABSTRACT: The objective of this work was to evaluate the reproductive performance of ewes exposed to a photoperiodic regimen consisting of continuous alternating 4-mo periods of long days (LD: 16 h of light/d) and short days (SHD: 8 h of light/d) in an accelerated lambing program of 3 lambings in 2 yr. A total of 211 prolific Rideau Arcott ewes were assigned to the photoperiodic treatment, whereas 37 ewes were maintained under natural annual variation in day length (control group). Ewes under the photoperiod regimen were divided into 4 subgroups (A, B, C, D). All these groups of ewes were exposed to the same light regimen, but the LD and SHD light sequences were staggered by 2 mo to permit the evaluation of the effect of time and season of mating on performance of the ewes treated with the photoperiod. The control ewes were treated with intravaginal sponges in the out-of-season breeding periods (conventional approach). Each group of ewes was studied over 3 reproductive cycles. Two groups of rams exposed to alternating 2-mo sequences of LD and SHD were used for mating. The short mean interval between ram introduction and conception for the groups exposed to artificial photoperiod (9.4 d) confirmed the effectiveness of the treatment to induce intense sexual activity. For the 12 breeding periods studied (8 in outof-season and 4 in sexual season), fertility rate of the ewes treated with photoperiod, mated at various times of year, was 91.6%, which is comparable with the fertility normally seen in the natural breeding season. The number of lambs born/ewe remained constant across reproductive cycles and was greater in photoperiodtreated groups (2.81 vs. 2.27 for photoperiod and control groups, respectively; P = 0.0002). Groups exposed to photoperiod treatment obtained better fertility rate than the control group in out-of-season breeding (91.1 vs. 76.3%; P = 0.016). Ewes managed under the photoperiod regimen produced 1.38 lambings/yr and 69% of them lambed 3 times in 2 yr. Overall, the ewes in the photoperiodic treatment produced annually 3.78 lambs/ ewe. The reproductive performances achieved throughout the years indicate that the photoperiodic program tested, consisting of continuous alternating 4-mo periods of LD and SHD, allows control of the annual reproductive cycles in ewes.
Increasing levels of childhood obesity have raised concerns about the eating habits of children. The aim of the present study was to investigate meal and snack patterns and nutrient intakes of Scottish schoolchildren comparing term-time v. holidays and weekday v. weekends during term-time.As part of a national cross-sectional dietary survey of Scottish children conducted in 2006, a subsample of children aged 5-17 years completed a 4 d non-weighed-diet diary (n 156; eighty-one boys and seventy-five girls). These diaries were analysed to describe the frequency of meal and snack consumption per d and average daily nutrient intakes. Eating events were defined as meals or snacks, with each eating event being separated by a minimum of 30 min. The definition of meals and snacks was adapted from Kelly et al.(1) in which foods were coded into 'core' and 'non-core' foods. Meals were defined as an eating event containing one or more 'core' foods, while a snack contained no 'core' foods. The average number of meals and snacks eaten per d and the average daily nutrient intakes were compared between subgroups defined by age (5-11 years and 12-17 years), gender, term-time or holidays and weekdays or weekends.Comparison of term-time and holiday included intakes from only weekdays (excluding the weekend) and excluded children whose diary spanned term-time and holiday. The within-subject analysis comparing week and weekend days was based on diaries only completed during term-time (n 106).The median) number of eating events per child for the whole sample (n 156) was 5.3 (interquartile range (IQR) 4.8-6.0) per d, and comprised 3.3 (IQR 2.8-3.5) meals plus 2.0 (IQR 1.5-2.8) snacks. There were no significant differences in the number of meals and snacks eaten between age-groups or between term-time v. holiday subgroups. A significantly higher number of meals were eaten per d by boys (3.3 (IQR 3.0-3.5)) than by girls (3.0 (IQR 2.8-3.5); P = 0.032) in the whole sample. A significantly higher number of meals were eaten on weekdays (3.0 (IQR 3.0-3.7)) than weekends (3.0 (IQR 3.0-3.0); P = 0.015) and this pattern remained when data from term-time and holiday were combined. The Tables show the mean and 95 % confidence interval (CI) of average daily nutrient intakes for term-time v. holidays and weekdays v. weekends (term-time only). There were no significant differences in the average daily nutrient intakes between these groups (P < 0.05). Nutrient intake or frequency of meal and snack consumption among children in Scotland in the present study did not differ between term-time and holidays. Children tended to consume more meals on weekdays compared with weekends, but there was no difference in their average daily nutrient intake between these days.
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